MALOCCLUSIONS IN YOUNG ANIMALS

OH, WE PAYED LOTS OF $$$’S, WE NEED TO BREED HIM MALOCCLUSIONS

• Only three classes? Nope, this is not that easy. • While there are many types of malocclusion, therapy is required only if; 1. We see trauma to gingival or palatal tissue from malocclusion 2. Attrition or crown wear due to malocclusion 3. Dysphagia or difficulty eating •NEVER, EVER treat malocclusions to return the animal to perfect occlusion for esthetics or to return to showing. NORMAL OCCLUSION. THESE ARE HARD TO FIND CLASS 1 MALOCCLUSION

• Jaw lengths are appropriate • Most significant location to examine is the diastema, or space between maxillary third incisor and canine teeth • Mandibular canine tooth should occlude perfectly between the maxillary third incisor. • The mandibular canine tooth rarely is completely equidistant between, so we are really looking for trauma to buccal gingiva or attrition to maxillary or mandibular teeth. CLASS 1 MALOCCLUSION WITH LINGUOVERSION OF MANDIBULAR CANINE TEETH

MOST COMMON MALOCCLUSION NOTED Note palatine trauma CLASS 2 MALOCCLUSION

• Mandible is shorter than appropriate. • Most common ACTIONABLE event; linguoversion of mandibular canine teeth causing traumatic malocclusion • Rarely we will see palatal trauma due to incisor malocclusion SEVERE CLASS 2 MALOCCLUSION CLASS 3 MALOCCLUSION

• Mandible longer than appropriate • Most common ACTIONABLE event • Linguoversion of mandibular canine teeth • Rarely, we will see trauma to tongue, lingual tissue due to maxillary teeth CLASS 3 MALOCCLUSION CLASS 4 MALOCCLUSION

• AKA; Maxillary/mandibular asymmetry • Prior term was wry bite • Can be noted in; • Side to side direction; most common • Rostrocaudal direction • Dorsoventral direction • Most commonly noted secondary to TMJ fracture, but occasionally noted due to congenital abnormality • If severe, may require condylectomy MANDIBULAR/MAXILLARY ASYMMETRY IN THE SIDE TO SIDE DIRECTION NOT TERRIBLY COMMON

Right diastema Left; OOPS OK, WE COVERED THE INTELLECTUAL STUFF

• Linguoversion of mandibular canine teeth is by far the most common actionable malocclusion • Treated in stages, no quick, easy, one- stop therapy • As this is caused by jaw width, length discrepancy, this is considered an inherited trait LINGUOVERSION OF MANDIBULAR CANINE TEETH THERAPEUTIC PROCESS

• 1. Interceptive orthodontics • Extraction of deciduous mandibular canine teeth • Immediately, upon diagnosis of traumatic malocclusion • The earlier this is accomplished, the more likely we will be successful in treatment 2. This accomplishes two goals a. Immediate relief of pain due to traumatic malocclusion b. Creation of space at buccal aspect of adult mandibular canine teeth to allow possibility of tipping of mandibular canine teeth into diastema 3. Occasionally, extraction will allow lower jaw to grow rostrally. INTERCEPTIVE ORTHODONTICS CREATES SPACE FOR MOVEMENT OF ADULT CANINE TEETH CRITICAL SURGICAL POINTS

1.Get excellent pre-operative radiographs • -We often see curved roots or marked proximity to surrounding tooth buds 2.Make a generous flap - My recommendation is to perform surgical extraction for these - Closed extraction can often lead to retained tooth root fragments 3.BE GENTLE - This is not the time to be in a hurry - Deciduous teeth are dramatically fragile 4.Be aware or surrounding tooth buds • - Developing tooth buds are easy to traumatize 5.Free gingiva for tension free closure • - Tension will inevitably lead to flap failure 6.ALWAYS expose post-operative radiography • -Retained tooth root fragments will lead to treatment failure • - Root fragment do NOT dissolve INTECEPTIVE ORTHODONTICS

Gently incise attached gingiva Incise attached gingiva around tooth TENSION WILL RESULT IN FLAP FAILURE

Demonstration of lack of Fenestrate periosteum tension RADIOLOGY IS ESSENTIAL

Pre-operative; note proximity Note space produced by extraction of adult tooth buds as well as complete extraction BE CAREFUL

Interceptive orthodontics Retained tooth root causing Osteonecrosis of fragment from attempt to the Jaw extract NOW…WE WAIT

• When the adult mandibular canine teeth erupt to the height of the adult mandibular third incisor teeth we then acquire a ball or Kong toy of appropriate size. • It is important to find a ball that will place pressure on the canine teeth but will not place pressure on the incisor teeth. KONG THERAPY

Right way Wrong way BALL THERAPY THIS IS CRITICAL

• Set a timetable • Perform Kong or digital therapy as often as possible; q8 at minimum • Play tug-of-war for 5 minutes • HAVE A DEADLINE • Set up a treatment monitoring examination for 2 weeks • If mandibular canine teeth cusps are not buccal to maxilla and within diastema in 2 weeks, it is critical to move onto next step OK, WHAT NOW?

• If mandibular canine teeth cusps are not within diastema at 2 weeks • 1. Refer for application of acrylic or metal incline plane • 2. Coronal extensions • 3. Crown reduction and vital pulp therapy • 4. Extraction. This is the least desirable therapy. Use only if owner has been informed of options and declines due to cost. There is no medical reason to extract. GINGIVAL WEDGE CORONAL EXTENSIONS USING COMPOSITE RESIN OR BIS- ACRYL ACRYLIC POLYMER

Used when traumatic malocclusion is within a few mm of the mesial ridge. Must be removed It is critical to elliminate chewing when applied Work reasonably well A DIFFERETENT INTERCEPTIVE ORTHODONTICS ACRYLIC INCLINE PLANE CAST METAL INCLINE PLANE POST INCLINE PLANE CLASS II MALOCCLUSION (OVERSHOT) CROWN REDUCTION, PARTIAL PULPECTOMY, VITAL PULP THERAPY • -Used when mandibular canine teeth are present palatal to maxillary canine teeth (Class 2 malocclusion) • -Goal is to allow complete apex to form • -Performed under sterile conditions • -Must be radiographically monitored as restorations can fracture and leak years after successful • -Technical, tricky surgery CLASS TWO MALOCCLUSION WITH LINGUOVERSION OF MANDIBULAR CANINE TEETH NOTE SEVERITY OF CLASS TWO MALOCCLUSION MAKING ORTHODONTIC MOVEMENT DIFFICULT TRAUMATIC MALOCCLUSION IMMATURE ADULT MANDIBULAR RIGHT CANINE TOOTH VPT should allow this REDapex ARROW; to INCOMPLETE form. If APEXIFICATION the VPT subsequently fails, conventionalBLUE BAR; WIDE PULP endodontiaCANAL WITH ONLY PRIMARY is more DENTIN successful DENOTES IMMAT Uthan R E T O O T H apexification. POST FLOWABLE COMPOSITE RESTORATION RADIOGRAPH

YELLOW ARROWS; COMPOSITE RESTORATION GREEN ARROWS; GLASS IONOMER RED ARROWS; MTA LAYER SUCCESS; ONE YEAR POST VPT

Green arrows; pulp canal width, note bilateral symmetry and narrow width Red arrows; no periapical lucency OK, WE CAN DO OTHER ORTHODONTIA